<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="../js/jquery-1.8.3.min.js"></script>
    <script>
        //alert($("div").html())
        /*
        $(document).ready(function () {
         alert($("div").html())
         });
    */
        $(function(){
            alert($("div").html())
        });
    </script>
</head>
<body>
$(document).ready( )的简写。
     $(callback );

<div>aaa</div>


</body>
</html>